metrics: avoid overflow from bad sysfs value

A zram bug can create very large values for orig_data_size,
which causes an overflow.  Rather than fixing various kernel
versions, we work around the problem here.

BUG=chromium:686928
TEST=none

Change-Id: If3657091cff5727adf0dd2a15ccfa3f94095cc83
Reviewed-on: https://chromium-review.googlesource.com/439005
Commit-Ready: Luigi Semenzato <semenzato@chromium.org>
Tested-by: Luigi Semenzato <semenzato@chromium.org>
Reviewed-by: Kirtika Ruchandani <kirtika@chromium.org>
(cherry picked from commit f56f45d1b6ec53ed52dc88061d3d6b03ccc4bc15)
Reviewed-on: https://chromium-review.googlesource.com/468529
Reviewed-by: Luigi Semenzato <semenzato@chromium.org>
Commit-Queue: Luigi Semenzato <semenzato@chromium.org>
1 file changed